Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Pregnenolone 50 mg Ingredients & Drug Interactions

by Source Naturals

Pregnenolone 50 mg label
See full label image
Tablet Or Pill Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Pregnenolone 50 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Pregnenolone 50 mg is a dietary supplement by Source Naturals with 2 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 248 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin C, Pregnenolone. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Pregnenolone 50 mg by Source Naturals

Ask about any prescription or over-the-counter medication and we check it for interactions with Pregnenolone 50 mg by Source Naturals — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Pregnenolone 50 mg by Source Naturals

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product has 2 active ingredients: vitamin C and pregnenolone. Vitamin C is an essential nutrient that supports immune function and acts as an antioxidant.

Pregnenolone is a hormone precursor—your body can convert it into other hormones like estrogen, progesterone, and testosterone. The inactive ingredients are sorbitol, mannitol, cellulose gum, silicon dioxide, stearic acid, and magnesium stearate, which serve as fillers and binders.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Vitamin C deficiency — rated "Effective" (Vitamin C) (Natural Medicines).
  • On file: Hypercholesterolemia — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Anemia of chronic disease — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Atrial fibrillation — rated "Possibly Effective" (Vitamin C) (Natural Medicines).
  • On file: Laser skin resurfacing — rated "Possibly Effective" (Vitamin C) (Natural Medicines).

Vitamin C is effective for preventing and treating vitamin C deficiency. It's possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections, though the evidence for these uses isn't yet established.

For pregnenolone, the evidence we hold doesn't establish its effectiveness for any condition—the data rates it as having insufficient reliable evidence for alcohol use disorder, Alzheimer disease, autism spectrum disorder, back pain, bipolar disorder, and other conditions.

The evidence, ingredient by ingredient Vitamin C Pregnenolone

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal dietary and supplement doses, though very high doses can cause abdominal cramps, heartburn, osmotic diarrhea, nausea, and vomiting—especially above 2 grams daily. Kidney stones have been reported in people prone to them.

Pregnenolone is also generally well tolerated orally, but reported side effects include acne, agitation, diarrhea, drowsiness, hair loss, sweating, tremor, and in rare cases a photosensitivity-like rash. Because pregnenolone is a hormone with limited human safety data, it should be used only under guidance from a healthcare professional.

During pregnancy, the safety data advises against pregnenolone due to unknown risks, and while breastfeeding, there isn't enough safety information—avoid it. For vitamin C, normal amounts from food and prenatal vitamins are fine, but high-dose supplements should be avoided in pregnancy and lactation unless your doctor advises otherwise.

Side effects, ingredient by ingredient Vitamin C Pregnenolone

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Pregnenolone, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments.
  • For scale: 248 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your pharmacist if you're on estrogen-based medications (birth control pills, hormone replacement therapy), benzodiazepines (sedatives for anxiety), blood thinners like warfarin, thyroid medication like levothyroxine, chemotherapy drugs, HIV protease inhibitors like indinavir, aluminum-containing antacids, or the antipsychotic fluphenazine. Moderate interactions are documented for all of these drug types.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

If you take estrogens, benzodiazepines, blood thinners, thyroid medication, or chemotherapy drugs, you need to check this product with your pharmacist before starting. Pregnenolone is a hormone and requires professional supervision; don't use it in pregnancy or while breastfeeding without explicit medical guidance.

Talk to your pharmacist or doctor about whether this product fits your health picture.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 23, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Pregnenolone 50 mg, straight from the product label.

Brand Source Naturals
Barcode (UPC) 021078009252
Net contents 120 Tablet(s)
Market status On market
Date entered into DSLD Aug 23, 2023
DSLD ID 296156
Product type Non-nutrient/non-botanical
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Pregnenolone 50 mg by Source Naturals, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
Servings per container
120
UPC/BARCODE
021078009252
IngredientAmount% DV
Vitamin C21 mg35%
Pregnenolone50 mg--

Other ingredients: Sorbitol, Mannitol, Cellulose Gum, Silicon Dioxide, Stearic Acid, Magnesium Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

Dietary Supplement

Precautions

Warning: Not for use by individuals under the age of 18 years.

Do not use if you are pregnant, may become pregnant, or breastfeeding. Consult a physician or licensed qualified health care professional before using this product if you have, or have a family history of, prostate cancer, prostate enlargement, heart disease, low "good cholesterol (HDL), or if you are using any other dietary supplement, prescription drug, or over-the-counter drug.

Do not exceed recommended serving. Exceeding recommended serving may cause serious adverse heath effects. Possible side effects include acne, hair loss, hair growth on the face (in women), aggressiveness, irritability and increased levels of estrogen. Discontinue use and call a physician or licensed qualified health care professional immediately if you experience rapid heartbeat, dizziness, blurred vision, or other similar symptoms.

Using pregnenolone may elevate your DHEA levels, and DHEA can increase estrogen and testosterone levels. Read entire label before using.

Keep out of reach of children.

To report any adverse events call 1-800-332-1088

Do not use if either tamper-evident seal is broken or missing.

Keep out of the reach of children.

Suggested/Recommended/Usage/Directions

Directions: 1 tablet daily. 1/2 tablet may be sufficient for some people. Do not exceed 1 tablet per day. Do not take for more than 30 days without the advice of your physician, and have your blood hormone (estrogen, testosterone, DHEA) levels regularly assessed by your physician.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Brand IP Statement(s)

Copyright Source Naturals, Inc.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Pregnenolone 50 mg by Source Naturals label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Pregnenolone 50 mg label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Pregnenolone 50 mg by Source Naturals

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container120 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Vitamin C

Interacts with
207 drugs
21 mg per serving Form: Ascorbyl Palmitate

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Pregnenolone

Interacts with
82 drugs
50 mg per serving

Pregnenolone is a hormone your body makes naturally and a building block for other hormones like cortisol, DHEA, estrogen, and testosterone. It is sol...

Pregnenolone monograph & interactions

Other (inactive) ingredients: Sorbitol, Mannitol, Cellulose Gum, Silicon Dioxide, Stearic Acid, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pregnenolone 50 mg by Source Naturals Drug Interactions

Want to check YOUR meds against Pregnenolone 50 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
248Drugs
142 Moderate 106 Minor

Ingredients driving the most interactions

Vitamin C 207
Pregnenolone 82

Individual Drug Interactions

The ingredients in Pregnenolone 50 mg interact with 248 drugs. Click any drug to see the details.

2 of the 2 ingredients in Pregnenolone 50 mg interact with drugs. Each result below shows which ingredient is responsible. Vitamin C Pregnenolone

Each ingredient & the kinds of drugs it affects

For each ingredient in Pregnenolone 50 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions

Pregnenolone5 drug types · 82 drugs

Benzodiazepines

Concomitant use of pregnenolone may reduce the effects of benzodiazepines.
Very preliminary clinical research shows that chronic use of pregnenolone reduces sedative effects of diazepam when compared with chronic use of placebo. This effect may be related to the activity of pregnenolone at GABAA receptors.

Likelihood Probable Evidence B
Estrogens

Theoretically, taking pregnenolone might enhance the effects of estrogens.
Pregnenolone is a precursor for several steroid hormones, including estrogens.

Likelihood Possible Evidence D
Progesterone

Theoretically, taking pregnenolone might enhance the effects of progesterone.
In humans, some research shows that oral administration of pregnenolone can increase levels of progesterone. However, other research shows no effect on progesterone levels. It is possible the impact of pregnenolone on progesterone levels may be dose dependent.

Likelihood Possible Evidence D
Progestin

Theoretically, taking pregnenolone might enhance the effects of progestin.
Pregnenolone is a precursor for several steroid hormones, including progestin.

Likelihood Possible Evidence D
Testosterone

Theoretically, taking pregnenolone might enhance the effects of testosterone.
Pregnenolone is a precursor for several steroid hormones, including testosterone. However, preliminary clinical research shows that taking pregnenolone 30-500 mg orally daily for up to 8 weeks does not affect testosterone levels.

Likelihood Possible Evidence D
Pregnenolone full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Pregnenolone 50 mg, from the product label.

Source Naturals

Name
Source Naturals, Inc.
Street Address
P. O. Box 2118
City
Santa Cruz
State
CA
ZipCode
95062
Web Address
www.sourcenaturals.com
Pharmacist Counseling Corner

Pregnenolone 50 mg by Source Naturals: Common Questions

Does Pregnenolone 50 mg by Source Naturals interact with any medications?
Yes. Based on its ingredients, Pregnenolone 50 mg has a known interaction with 248 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pregnenolone 50 mg contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm on birth control pills?
No—not without checking with your pharmacist first. Vitamin C in this product can increase blood levels of estrogens by up to 55%, which could affect how well your birth control works or increase side effects. Your doctor or pharmacist needs to evaluate your specific situation.
What is pregnenolone used for?
Pregnenolone is a hormone precursor your body can convert into other hormones. The evidence we hold doesn't establish its effectiveness for any specific condition, though it's been studied for uses like Alzheimer disease, bipolar disorder, and back pain. It should only be used under professional guidance.
Can I take this while pregnant or breastfeeding?
No to pregnenolone—the safety data advises against it in pregnancy due to unknown risks, and avoid it while breastfeeding because there isn't enough safety information. For vitamin C, normal amounts from food and prenatal vitamins are fine, but high-dose supplements should be avoided unless your doctor advises otherwise.
What are the side effects of pregnenolone?
Most common side effects include acne, agitation, diarrhea, drowsiness, hair loss, sweating, and tremor. Rare cases of a rash resembling a photosensitivity reaction have been reported. Tell your doctor if you develop any of these.
Is this safe if I take thyroid medication?
Vitamin C can increase how much of your thyroid medication (like levothyroxine) gets absorbed, which may change your dose needs. Your doctor should monitor your thyroid levels if you start this product, and your medication dose might need adjustment.
What if I'm on a benzodiazepine like Xanax or Valium?
Pregnenolone in this product may reduce how well benzodiazepines work—preliminary research shows chronic use of pregnenolone reduces their sedative effects. Check with your pharmacist before taking this product.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Pregnenolone 50 mg label
Go deeper

The Full Monographs Behind Pregnenolone 50 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Pregnenolone

Interacts with 82 drugs

Pregnenolone is a hormone your body makes naturally and a building block for other hormones like cortisol, DHEA, estrogen, and testosterone. It is sold as a supplement for memory, mood, and...

Read the full Pregnenolone monograph →
Sources

Sources & How We Checked

Pregnenolone 50 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 57 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
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See these in context on the Vitamin C monograph →

Pregnenolone 6 references
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See these in context on the Pregnenolone monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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